Anorexia: signs, causes, treatment

The eating disorder anorexia nervosa leads to dangerous underweight. More about typical symptoms and therapy

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What is anorexia?

In a nutshell: what is anorexia?

Anorexia (anorexia nervosa) is one of the eating disorders. Experts estimate that around half a percent of women between the ages of 15 and 35 worldwide are anorexic. Significantly more women than men are affected. Often times, the disease begins in teenagers or early adulthood.

A typical sign of anorexia is self-induced weight loss or even underweight. Affected people starve, limit their choice of food or exercise excessively, some vomit or abuse laxatives to lose weight. Anorexics see their bodies distorted, suffer from a body schema disorder: Although they are slim, they fear being too fat or gaining weight again quickly.

Malnutrition can have negative, sometimes life-threatening, consequences. Early therapy is important. Psychotherapy has proven itself in the treatment of anorexia. The eating disorder is not a phenomenon of modern times, but was first described about 150 years ago.

Signs: What are the symptoms of anorexia?

The most noticeable feature of the disease is underweight, which - often within a short period of time - is self-induced. Experts distinguish different forms of anorexia:

1) Restrictive Anorexia Nervosa: The entry into the eating disorder often begins with a diet. People try to lose weight in different ways. You are starving or exercising excessively. Typically, they avoid foods that are particularly high in calories. Some younger girls or boys only try to maintain their current body weight and not gain any further, even though they are in the growth phase. So they gain too little weight for their age.

2) Purging type (from the English word "to purge" = to purge): Sufferers use laxatives or dehydrating agents, for example, or they vomit after eating in order to reduce their weight or to avoid weight gain. Long periods of fasting can also lead to food cravings with binge eating and subsequent vomiting (bulimic form of anorexia).

Other signs of anorexia:

  • Body schema disorder: Despite being underweight, anorexics perceive themselves to be too fat. Experts call this distortion of perception body schema disorder. Anorexic people usually do not feel sick or in need of treatment
  • Fear of weight gain: Anorexics check their weight very carefully, sometimes several times a day. They have an exaggerated fear of gaining weight
  • Eating rituals: Most anorexic people find it very difficult to eat. For example, they eat noticeably slowly, poke at food, drink plenty of water to fill their stomachs, or follow self-made eating rituals. Many avoid eating with others or want to cook for family members or friends without eating in order to maintain control over meals. You deal a lot with nutritional issues, for example swap cooking recipes, but cannot prepare meals in an enjoyable way.
  • Thoughts revolve around weight and food: the subjects of weight, calories and weight loss dominate the mind of the patient. Many anorexics withdraw from social life, let contacts with friends fall asleep, neglect other interests

The term "anorexia" literally means "loss of appetite", which is actually not entirely accurate. Because many anorexic people initially have a normal or even large appetite. In a state of malnutrition, however, the balance between the body's own messenger substances can be disturbed, so that the feeling of hunger is completely lost.

Possible consequences: What are the physical effects of anorexia?

The severe weight loss and the associated deficiency in supply are not without consequences for the organism in the long run.

Metabolism: The lack of energy causes the body to switch to "low flame". Body temperature drops, blood pressure drops, the heart beats slowly. Many anorexic people freeze quickly and have cold hands and feet. The gastric emptying is delayed by the reduced food intake and the intestinal contents need more time to pass through the intestines - constipation easily occurs. If there is a severe protein deficiency, fluid is deposited in the tissue (edema).

Skin and hair: Anorexic people often have dry and flaky skin. In addition, the nails can become brittle and the hair thinning or even falling out. On some parts of the body, such as the arms, back and face, a downy, fine hair (lanugo hair) develops. This is an attempt by the body to regulate its heat balance. Because the subcutaneous fatty tissue shrinks, the veins protrude visibly, and the skin on the hands and feet has a bluish shimmer.

Bones, muscles, teeth: If the body receives less energy than it consumes, it breaks down muscle mass. If the body receives too few nutrients over a longer period of time, symptoms of deficiency occur. Growth and development are slowed down or even inhibited. In connection with a lack of calcium, phosphate and vitamin D, bone metabolism disorders occur. The bones become brittle, known as osteoporosis. Teeth suffer too, especially when vomiting is frequent. There is a risk of tooth decay or even tooth loss.

Brain: In a state of malnutrition, a loss of brain tissue is observed. This loss manifests itself in particular in a widening of the cerebral furrows and an enlargement of the inner brain chambers that carry the cerebral water. The loss of brain tissue goes hand in hand with a loss of brain performance. With normalization of weight, the brain atrophy regresses in most cases.

Salt balance: Extreme starvation, vomiting or the abuse of laxatives can upset the body's salt balance. There is a lack of vital electrolytes. Severe potassium deficiency is particularly problematic because it triggers dangerous cardiac arrhythmias.

Immune system: The immune system also suffers from a lack of supply. The body becomes more prone to infection. In the case of very severe anorexia, they are a common cause of death, as are cardiac complications.

Much of the physical effects regress once a healthy weight is reached. Some consequences, such as the loss of bone mass, may no longer be completely reversible.

Why do you miss your period when you have anorexia?

Typically, the level of sex hormones drops in anorexia. Affected people often lose interest in sexuality, male anorexics can suffer from erectile dysfunction. In women affected, their menstrual periods stop when they lose weight - provided they do not take the "birth control pill", which simulates healthy hormone production in the body. After the normalization of the weight, the menstrual period starts again. Pregnancy may then be possible again.

Causes: How does anorexia come about?

It is not known exactly why anorexia develops. Experts assume that various triggers play a role in the eating disorder and can influence one another:

Investment-related factors: relatives of those affected are at an increased risk of developing anorexia. Presumably, different genes contribute to this risk. It increases with closer kinship.

Biological factors: messenger substances and hormones that act on the eating center in the brain are probably important in the development, but certainly in the maintenance of anorexia. Recent research shows that brain function in anorexic people can be altered in certain brain networks. For example, starvation has a strong positive effect on anorexic people. It is still unclear what significance these changes have and whether they are the cause or consequence of the disease.

Psychological factors: Some personality traits such as perfectionism, fearfulness or obsession, a weak self-esteem or the feeling of having to meet very high standards can contribute to the development of the disease. Anorexia often begins during puberty. The disease can be an expression of the fact that those affected do not feel up to the demands of this phase of life. The feeling of losing control of certain areas of life on the one hand and the experience of being able to take control of nutrition and eating independently on the other hand can create a feeling of autonomy. Some of those affected also have serious traumas such as sexual abuse in their biography.

Social reasons: In the western industrialized countries in particular, advertising and media convey unrealistic ideals of beauty. Young people in particular during puberty and adolescence can feel pressured as a result. Many sufferers report dieting or very controlled eating habits before anorexia developed.

How is the diagnosis made?

There is no single test that shows anorexia.

In conversations, the doctor gets the most accurate picture possible. He asks about eating habits, your own view of your body, your weight history and the weight you are aiming for. He also tries to identify any accompanying mental illnesses, such as depression or an anxiety disorder. In order to record typical symptoms more precisely, questionnaires and structured interviews are used.

Body mass index (BMI) is the benchmark for assessing body weight. It is calculated from your height and weight. In the case of anorexia, it is below 18.5 kg / m2 with the new classification systems. If you are under 18 years of age, the BMI percentile curves are used.

A thorough physical examination is important, possibly supplemented by further checks such as ultrasound or blood tests. On the one hand, the doctor must rule out that the underweight is caused by a physical illness, for example a thyroid disorder. On the other hand, he must examine whether deficiency symptoms have already set in.

If necessary, the doctor will be referred to a specialist, for example to a psychosomatic facility with a focus on eating disorders or to a child and adolescent psychiatric clinic for children and adolescents.

Therapy: How is anorexia treated?

The earlier therapy begins, the better the chances of recovery. The first point of contact - depending on your age - can be, for example, your family doctor, a pediatrician, a psychotherapist, a special outpatient clinic for eating disorders or a counseling center. She can help with the choice of a suitable therapy offer and the question of how the health insurance company will assume the costs.

The Federal Center for Health Education, for example, lists advice centers at It also offers an information phone on 0221 89 20 31.

Outpatient or inpatient therapy?

Anorexia can be treated on an outpatient, partial or inpatient basis in the clinic. Follow-up care often follows, for example in a day clinic or in the form of regular follow-up examinations. There are also therapeutic residential groups. Which offer is most suitable depends on the individual situation and ideally depends on the wishes of those affected.

If the underweight has reached threatening proportions or if the physical effects are already very serious, then inpatient treatment is advisable. As a rule, it is continued on an outpatient basis. Therapy in the clinic may also be necessary if there are complications or accompanying illnesses, such as depression, or if outpatient therapy is unsuccessful.

Treatment may also have to take place against a patient's will. However, this should only be done as a last option in absolute emergencies, if the lack of treatment results in a life-threatening situation or another serious psychosocial risk. The aim is always for the person affected to begin treatment of their own free will and conviction. If food intake is not possible or only possible under very stressful circumstances, feeding through a tube may be necessary temporarily.

How long will the treatment take?

The duration of therapy can vary from case to case. It can be anywhere from a few weeks to several months. Longer periods of time should be planned for aftercare. It may take several years to complete.

Building blocks of therapy

In the treatment of anorexia, different specialists often work together, for example doctors, psychotherapists, psychologists, nutritionists or dietitians. You should specialize in the treatment of eating disorders. The treatment consists of several interlinked elements:

  • The weight needs to be lifted and stabilized back to a healthy range. That is usually the most urgent task. It is also important to compensate for deficiency symptoms
  • Those affected learn to eat healthily and regularly again, to listen to signals from their own body, to be able to enjoy the food again - this often happens together with other affected persons and under the guidance of specialized nutrition experts. Nutritional therapy alone is not enough as therapy
  • In psychotherapy, the triggers and sustaining factors of the eating disorder are discussed, and sustainable strategies for everyday life and methods for relapse prevention are developed. Affected people practice, for example, to better feel their needs and to promote strengths and abilities. Targeted behavior training can make people safer when dealing with other people and enable them to better express feelings towards others. The therapy can take place individually or in a group. It is essential for children and young people to include the family. In the case of older sufferers, it makes sense to involve a partner or family.

Medicines can support the therapy in certain cases, for example in the case of simultaneous psychological problems.

Anorexia: course and prognosis

The course of the disease can vary from person to person. An exact forecast is usually not possible.

The prognosis is considered better if

  • the disease has not been around for very long
  • he underweight is not too pronounced
  • there are no other mental illnesses such as addictions.

Those affected who also abuse laxatives or vomit in order to lose weight (purging type, see section Symptoms) have to fear more pronounced negative physical consequences of the disease. Overall, the prognosis for them is slightly worse than for restrictive anorexia.

Around 50 percent of patients manage to overcome anorexia well.In about 25 percent of those affected, the disease is chronic or so unfavorable that the patients die as a result of anorexia (5%). The causes of death are on the one hand physical complications such as heart problems or infections. On the other hand, the risk of suicide is also increased.

Illness relapses are common. They occur in around a third of those affected, even after a long time, for example in critical life situations. In some of the patients the anorexia is chronic, they experience better and worse phases. For those affected, their relatives and therapists, treatment can be very challenging, especially when the willingness of those affected to treat is lacking or fluctuating very strongly.

For some people, the eating disorder is replaced later in life by another mental disorder, such as obsessive-compulsive disorder, depression, drug or alcohol abuse. Anorexia can also progress to another type of eating disorder, such as bulimia.

Anorexia: What Can Parents, Relatives, Friends Do?

If you suspect a relative or friend may have an eating disorder, you should talk to them. Avoid criticism, reproach, or well-intentioned advice. Describe the behavior changes you have noticed and express that you are concerned. The weight does not have to be the focus at first.

If possible, try to get the person affected to contact a counseling center or a doctor without putting them under pressure. Offer your support.

Parents are responsible for the health of their minor child. For them, the situation can be particularly complicated. Relatives who are unsure can also turn to a counseling center. If you already classify the situation as critical, you should not hesitate to contact a doctor.

Anorexia is often a major challenge for relatives and requires a lot of patience and perseverance. They may blame themselves for the illness, feel helpless, or angry. It can be relieved to obtain information about anorexia from experts as much as possible and to support those affected with therapy. However, relatives cannot take on the role of therapist. The exchange in a self-help group can also be helpful.

Information & advice: Where can I get help?

Anonymous telephone advice is available, for example, from the Federal Center for Health Education
Phone number 0221 89 20 31
Monday to Thursday 10 a.m. to 10 p.m.
Friday to Sunday 10 a.m. to 6 p.m.

More information is available online at:

Federal Center for Health Education (BZgA):

[]ANAD e. V .:

Federal Ministry of Health: Questions and answers on the subject of eating disorders

[] Federal Association of Eating Disorders e.V.

[] Self-help groups for those affected or their relatives, e.g. via (national contact and information point for the suggestion and support of self-help groups)

Private lecturer Dr. Lars Wöckel

© W & B / private

Consulting expert

Private lecturer Dr. Lars Wöckel, MHBA, born in 1963, studied medicine at the Universities of Aachen and Bonn. In 1991 he worked at the Westphalian Clinic for Psychiatry in Dortmund, and in 1993 research assistant at the Institute for Pathology at the University of Cologne. He obtained his doctorate in 1994. med. (Neuroanatomy) in Aachen and from 1994 worked as a scientific assistant at the Institute for Brain Research at the University of Tübingen. From 1997 he worked at the Central Institute for Mental Health at the University of Heidelberg in Mannheim in the eating disorders working group. From 2002 he was senior physician at the clinic for psychiatry and psychotherapy for children and adolescents at the University of Frankfurt / Main and head of the eating disorder clinic. He has refused an appointment to a professorship at the University of Western Australia, Perth. From 2008 he worked as a senior physician at the Clinic for Child and Adolescent Psychiatry and Psychotherapy at the University Hospital of RWTH Aachen University with a focus on eating disorders. Since 2010 he has been chief physician at the Center for Child and Adolescent Psychiatry and Psychotherapy at Clienia Littenheid AG, Switzerland. He is a member of several societies, including DGKJP, DGESS, ÖGES, SGKJPP, DÄVT, Competence Network Eating Disorders, as well as a board member of the Swiss Society for Eating Disorders (SGES).


Patient guideline "Diagnostics and Treatment of Eating Disorders", 1st edition 2015

S3 guideline "Diagnostics and Therapy of Eating Disorders", as of 5/2018,

Eating disorders, information for parents, relatives and teachers, BZgA, as of 08/2011

Stephan Herpertz, Martina de Zwaan, Stephan Zipfel Eds., "Handbook Eating Disorders and Obesity", 2nd edition 2015, Springer Verlag

Sara F Forman, MD, "Eating disorders: Overview of epidemiology, clinical features, and diagnosis," ed. UpToDate. Waltham, MA: UpToDate Inc. (Retrieved October 2018)

Philip Mehler, MD, "Anorexia nervosa in adults and adolescents: Medical complications and their management," ed. UpToDate. Waltham, MA: UpToDate Inc. (Retrieved October 2018)

Diane Klein, MD, Evelyn Attia, MD, "Anorexia nervosa in adults: Clinical features, course of illness, assessment, and diagnosis," ed. UpToDate. Waltham, MA: UpToDate Inc. (Retrieved October 2018)

Important NOTE:
This article contains general information only and should not be used for self-diagnosis or self-treatment. He can not substitute a visit at the doctor. Unfortunately, our experts cannot answer individual questions.